This invention relates to a flexible tube-type throttling valve assembly particularly useful in gas pressure control.
In a preferred configuration, an expansible tube is carried on a core sleeve which is shaped for easy and economical construction and assembly. The sleeve has axially spaced inlet and outlet openings with an intermediate barrier preventing axial flow through the sleeve. This sub-assembly is inserted into the body of the valve and seated on bosses provided in the valve and the cover member. A chamber for control fluid is provided in the body around the flexible tube, and fluid passageway means is provided from upstream of the valve to transmit the upstream fluid to the chamber. In this passageway is an automatically varying flow restrictor for controlling the rate of admission of fluid to the chamber. In addition, a passageway to the downstream side of the valve, controlled by pilot means, regulates the rate of outflow of fluid from the chamber.